Failed to bind properties under 'spring.datasource.type' to java.lang.Class(javax.sql.DataSource)

异常：

2020-01-14 10:07:01.352  WARN 11568 --- [  restartedMain] ConfigServletWebServerApplicationContext : Exception encountered during context initialization - cancelling refresh attempt: org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'dataSource' defined in class path resource [org/springframework/boot/autoconfigure/jdbc/DataSourceConfiguration$Generic.class]: Unsatisfied dependency expressed through method 'dataSource' parameter 0; nested exception is org.springframework.boot.context.properties.ConfigurationPropertiesBindException: Error creating bean with name 'spring.datasource-org.springframework.boot.autoconfigure.jdbc.DataSourceProperties': Could not bind properties to 'DataSourceProperties' : prefix=spring.datasource, ignoreInvalidFields=false, ignoreUnknownFields=true; nested exception is org.springframework.boot.context.properties.bind.BindException: Failed to bind properties under 'spring.datasource.type' to java.lang.Class<javax.sql.DataSource>
2020-01-14 10:07:01.356  INFO 11568 --- [  restartedMain] o.apache.catalina.core.StandardService   : Stopping service [Tomcat]
2020-01-14 10:07:01.381  INFO 11568 --- [  restartedMain] ConditionEvaluationReportLoggingListener : 

Error starting ApplicationContext. To display the conditions report re-run your application with 'debug' enabled.
2020-01-14 10:07:01.386 ERROR 11568 --- [  restartedMain] o.s.b.d.LoggingFailureAnalysisReporter   : 

***************************
APPLICATION FAILED TO START
***************************

Description:

Failed to bind properties under 'spring.datasource.type' to java.lang.Class<javax.sql.DataSource>:

    Property: spring.datasource.type
    Value: com.alibaba.druid.pool.DruidDataSource
    Origin: class path resource [application.properties]:25:24
    Reason: No converter found capable of converting from type [java.lang.String] to type [java.lang.Class<javax.sql.DataSource>]

Action:

Update your application's configuration

Disconnected from the target VM, address: '127.0.0.1:51477', transport: 'socket'

Process finished with exit code 0

解决办法：
pom里加入依赖

<dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>druid</artifactId>
            <version>1.0.20</version>
 </dependency>

这就OK了